The Low Cut filter (commonly known as a high-pass filter) works on the lower frequencies of the audio signal (20 Hz to 1 kHz). The Low Cut filter is often used to reduce low frequency noise such as rumble. For example, when recording vocals it is common to use a low cut filter at about 60 to 80 Hz for this purpose. By specifying a frequency for the low EQ, you set a cutoff frequency. Frequencies above the cutoff frequency pass through unaffected. Frequencies below the cutoff frequency are attenuated at a constant rate, depending on the Ratio setting. The default cutoff frequency setting is 80 Hz with a Q value of 0.71.

The following diagram illustrates the result of limiting gain around the specified frequency of 500 Hz using the Low Cut filter with a lower Q setting of 0.35.

The following diagram illustrates the result of limiting gain around the specified frequency of 500 Hz using the Low Cut filter with a higher Q setting of 0.80.